Effect of selective capsulorrhaphy on the passive range of motion of the glenohumeral joint

Arthroscopic findings after manipulation under anesthesia in idiopathic capsulitis of the shoulder: A prospective study

BACKGROUND

Manipulation under anesthesia (MUA) of the shoulder joint is a commonly used method for the treatment of adhesive capsulitis. Though it has been known to be associated with a variety of complications, there is a paucity of studies describing the arthroscopic findings after MUA.

AIM

To describe the arthroscopic findings in patients with idiopathic adhesive capsulitis of the shoulder after MUA.

METHODS

We recruited 28 patients with idiopathic adhesive capsulitis who underwent arthroscopic capsular release. Manipulation of the shoulder was performed under anesthesia in all of these patients before capsular release. Intra-articular findings were recorded during arthroscopic capsular release in these patients.

RESULTS

All patients showed the presence of synovitis. Twenty-seven patients showed tears in the capsule on the anterior aspect. One patient had an avulsion of the anterior rim of the glenoid and labrum following the manipulation. Four patients had partial rotator cuff tears, and one patient showed a superior labrum anterior posterior lesion, which was not diagnosed preoperatively on magnetic resonance imaging.

CONCLUSION

MUA leads to rupture of the capsule, which is the desired outcome. However, the site of rupture of the capsule is dependent on the maneuvers of MUA. In addition, partial tears of the rotator cuff and osteochondral fractures of the glenoid can also occur.

The Arthroscopic Trillat Procedure Is a Valuable Treatment Option for Recurrent Anterior Instability in Young Athletes With Shoulder Hyperlaxity

PURPOSE

The purpose of this study is to report the outcomes of the all-arthroscopic Trillat procedure, combined with capsular plication, for the treatment of recurrent anterior instability in young athletes with shoulder hyperlaxity (external rotation >90°).

METHODS

We performed a retrospective evaluation of patients with recurrent anterior instability and shoulder hyperlaxity who underwent an arthroscopic Trillat between 2009 and 2019. Patients with concomitant rotator cuff lesions or voluntary or multidirectional instability were excluded. The osteotomized coracoid was fixed above the subscapularis with a cannulated screw or a suture button; a capsular plication was systematically associated. We followed patients with x-rays, computed tomography scans, and Subjective Shoulder Value, visual analog scale, Walch, Constant, and Rowe scores. Mean follow-up was 56 months (24-145).

RESULTS

Twenty-eight consecutive patients (30 shoulders) with a mean age of 25 years were identified, and all met criteria. The main finding under arthroscopy was a "loose shoulder" with anteroinferior capsular redundancy and no or few (10%) labrum tears, glenoid erosion (13%), or Hill-Sachs lesions (10%). At last follow-up, 90% of the shoulders (27/30) were stable, and 79% (19/24) of the patients practicing sports returned to their preinjury activity level. The Walch-Duplay and Rowe scores improved from 54 (38-68) to 81 (4-100) and 55 (30-71) to 84 (45-100), respectively, P < .001.

CONCLUSIONS

The arthroscopic Trillat is an effective procedure for the treatment of recurrent anterior instability in young athletes with shoulder hyperlaxity but no substantial humeral or glenoid bone loss, allowing return to overhead/contact sports.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Influence of joint volume on range of motion after arthroscopic rotator cuff repair

BACKGROUND

Capsular contracture is a well-known etiology in the primary stiff shoulder; thus capsular contracture and resultant decreased joint volume could lead to postoperative stiffness, which is a commonly reported morbidity after arthroscopic rotator cuff repair (ARCR). The purpose of this study was (1) to quantify the joint volume (total joint volume and each quadrant compartmental volume) using computed tomography arthrography (CTA) and (2) to demonstrate the relationship between joint volume and postoperative range of motion (ROM) after ARCR.

MATERIALS AND METHODS

Eighty-three patients (60 ± 5.11 years, men = 26, women = 57) who had undergone ARCR between January 2015 to December 2020 due to small to medium full-thickness tear and followed by CTA 6 months postoperatively were retrospectively reviewed. An image reconstruction program (3D Slicer, version 4.11.2 software) was used to calculate the joint volume (total joint volume and quadrant compartment joint volumes; anteroinferior, anterosuperior, posterosuperior and posteroinferior). For shoulder ROM, data including scaption (Sc), external rotation on side (ERs), external rotation at 90° (ER90), and internal rotation on back (IRb) were collected 6 months postoperatively. An evaluation of the correlation between joint volume and each shoulder motion was performed.

RESULTS

There were moderate correlations between the total joint volume and each motion (Sc: Pearson coefficient, 0.32, p = 0.0047; ERs: Pearson coefficient, 0.24, p = 0.0296; ER90: Pearson coefficient, 0.33, p = 0.0023; IRb: Pearson coefficient, 0.23, p = 0.0336). Among the quadrant compartments, the anteroinferior (Sc: Pearson coefficient, 0.26, p = 0.0199; ERs: Pearson coefficient, 0.23, p = 0.0336; ER90: Pearson coefficient, 0.25, p = 0.0246; IRb: Pearson coefficient, 0.26, p = 0.0168) and posterosuperior (Sc: Pearson coefficient, 0.24, p = 0.029; ER90: Pearson coefficient, 0.29, p = 0.008; IRb: Pearson coefficient, 0.22, p = 0.0491) and posteroinferior (Sc: Pearson coefficient, 0.30, p = 0.0064; ER90: Pearson coefficient, 0.29, p = 0.0072) showed moderate correlations with each shoulder motion.

CONCLUSION

Total joint volume, anteroinferior compartment joint volume, posterosuperior compartment joint volume and posteroinferior compartment joint volume were related to postoperative ROM after ARCR. Perioperative methods to increase the joint volume, especially the anteroinferior, posterosuperior and posteroinferior parts of the capsule may prevent postoperative stiffness after ARCR.

LEVEL OF EVIDENCE

Level III; Retrospective Case-Control Study.

Dislocation Arthropathy of the Shoulder

Glenohumeral osteoarthrosis (OA) may develop after primary, recurrent shoulder dislocation or instability surgery. The incidence is reported from 12 to 62%, depending on different risk factors. The risk of severe OA of the shoulder following dislocation is 10 to 20 times greater than the average population. Risk factors include the patient’s age at the first episode of instability or instability surgery, bony lesions, and rotator cuff tears. For mild stages of OA, arthroscopic removal of intraarticular material, arthroscopic debridement, or arthroscopic arthrolysis of an internal rotation contracture might be sufficient. For severe stages, mobilization of the internal rotation contracture and arthroplasty is indicated. With an intact rotator cuff and without a bone graft, results for anatomical shoulder arthroplasty are comparable to those following primary OA. With a bone graft at the glenoidal side, the risk for implant loosening is ten times greater. For the functional outcome, the quality of the rotator cuff is more predictive than the type of the previous surgery or the preoperative external rotation contracture. Reverse shoulder arthroplasty could be justified due to the higher rate of complications and revisions of non-constrained anatomic shoulder arthroplasties reported. Satisfactory clinical and radiological results have been published with mid to long term data now available.

Platelet-rich plasma as a potential prophylactic measure against frozen shoulder in an in vivo shoulder contracture model

INTRODUCTION

Frozen shoulder (adhesive capsulitis) is a common painful and functionally-limiting disease affecting around 2% of the population. So far, therapeutic options are limited and often unsatisfactory. Platelet-rich plasma (PRP) has been used as a treatment option in other orthopedic diseases since it contains growth factors that stimulate tissue repair. So far, the effect of PRP on frozen shoulder lacks evidence. We hypothesized that PRP may be valuable in the prophylaxis and treatment of secondary frozen shoulder due to capsular remodeling.

MATERIALS AND METHODS

An experimental study of an in vivo frozen shoulder model was conducted. Twenty Sprague-Dawley rats underwent surgery in which the body of the scapula was connected to the humerus with a high-strength suture. Two groups of 8 weeks survival time were allocated; a treatment group with one intraoperative injection of PRP into the glenohumeral joint (n = 10) and a control group without PRP (n = 10). The primary outcome was the structural change in the posterior synovial membrane of the posterior and inferior part of the glenohumeral joint using a semi-quantitative grading from 0 (lowest) to 3 (highest).

RESULTS

The posterior synovial membrane structural changes were significantly lower in the PRP group (median = 1 [interquartile range (IQR) = 0-1]) compared to controls (median = 2 [IQR = 1-3]) (p = 0.028). There were no differences for the remaining synovial membrane changes and fibrous capsule responses between groups.

CONCLUSIONS

In this in vivo shoulder contracture model, PRP injections seem to reduce the histological severity grade of some parts (i.e., posterior synovial membrane changes) of the secondary frozen shoulder without causing any side effects. It may be considered to investigate this effect further in future studies as a potential prophylaxis of secondary frozen shoulder (e.g., in operated or immobilized shoulders) or as a treatment option for patients with frozen shoulder in the early stage.

Simulating the effect of glenohumeral capsulorrhaphy on kinematics and muscle function

This study aimed to use a predictive simulation framework to examine shoulder kinematics, muscular effort, and task performance during functional upper limb movements under simulated selective glenohumeral capsulorrhaphy. A musculoskeletal model of the torso and upper limb was adapted to include passive restraints that simulated the changes in shoulder range of motion stemming from selective glenohumeral capsulorrhaphy procedures (anteroinferior, anterosuperior, posteroinferior, posterosuperior, and total anterior, inferior, posterior, and superior). Predictive muscle-driven simulations of three functional movements (upward reach, forward reach, and head touch) were generated with each model. Shoulder kinematics (elevation, elevation plane, and axial rotation), muscle cost (i.e., muscular effort), and task performance time were compared to a baseline model to assess the impact of the capsulorrhaphy procedures. Minimal differences in shoulder kinematics and task performance times were observed, suggesting that task performance could be maintained across the capsulorrhaphy conditions. Increased muscle cost was observed under the selective capsulorrhaphy conditions, however this was dependent on the task and capsulorrhaphy condition. Larger increases in muscle cost were observed under the capsulorrhaphy conditions that incurred the greatest reductions in shoulder range of motion (i.e., total inferior, total anterior, anteroinferior, and total posterior conditions) and during tasks that required shoulder kinematics closer to end range of motion (i.e., upward reach and head touch). The elevated muscle loading observed could present a risk to joint capsule repair. Appropriate rehabilitation following glenohumeral capsulorrhaphy is required to account for the elevated demands placed on muscles, particularly when a significant range of motion loss presents.

Mapping of the Inferior Glenohumeral Ligament for Suture Pullout Strength: A Biomechanical Analysis

Background

Suture pullout during rehabilitation may result in loss of tension in the inferior glenohumeral ligament (IGHL) and contribute to recurrent instability after capsular plication, performed with or without labral repair. To date, the suture pullout strength in the IGHL is not well-documented. This may contribute to recurrent instability.

Purpose/Hypothesis

A cadaveric biomechanical study was designed to investigate the suture pullout strength of sutures in the IGHL. We hypothesized that there would be no significant variability of suture pullout strength between specimens and zones. Additionally, we sought to determine the impact of early mobilization on sutures in the IGHL at time zero. We hypothesized that capsular plication sutures would fail under low load.

Study Design

Descriptive laboratory study.

Methods

Seven fresh-frozen cadaveric shoulders were dissected to isolate the IGHL complex, which was then divided into 18 zones. Sutures in these zones were attached to a linear actuator, and the resistance to suture pullout was recorded. A suture pullout strength map of the IGHL was constructed. These loads were used to calculate the load applied at the hand that would initiate suture pullout in the IGHL.

Results

Mean suture pullout strength for all specimens was 61.6 ± 26.1 N. The maximum load found to cause suture pullout through tissue was found to be low, regardless of zone of the IGHL. Calculations suggest that an external rotation force applied to the hand of only 9.6 N may be sufficient to tear capsular sutures at time zero.

Conclusion

This study did not provide clear evidence of desirable locations for fixation in the IGHL. However, given the low magnitude of failure loads, the results suggest the timetable for initiation of range-of-motion exercises should be reconsidered to prevent suture pullout through the IGHL.

Clinical Relevance

From this biomechanical study, the magnitude of force required to cause suture pullout through the IGHL is met or surpassed by normal postoperative early range-of-motion protocols.

The Role of Remplissage in the Setting of Shoulder Instability

Recurrent anterior shoulder instability is a multifactorial problem for which many solutions exist. Often, the bony surface area of the humeral head and the glenoid needs to be addressed surgically. For large, engaging humeral head defects associated with <25% glenoid bone loss, a remplissage procedure can effectively "fill in" the humeral defect with minimal postoperative morbidity. Remplissage is an effective biological solution that should be considered any time there is a humeral head defect which is contributing to glenohumeral instability.

Effects of self-stretching with mobilization on shoulder range of motion in individuals with glenohumeral internal rotation deficits: a randomized controlled trial

BACKGROUND

The combined effects of cross-body stretching and dorsal glide mobilization have not been examined previously, although both stretching and mobilization maneuvers are effective for improving shoulder range of motion (ROM). Thus, the aim of this study was to demonstrate the effects of stretching with mobilization (SWM) on glenohumeral (GH) internal rotation (IR) and horizontal adduction (HA) ROM.

METHODS

Forty individuals with GH IR deficits were randomized to perform simultaneous combined cross-body stretching and dorsal glide mobilization (SWM group, comprising 10 male and 10 female patients) or cross-body stretching alone (stretching group, comprising 10 male and 10 female patients). GH IR ROM, HA ROM, and shoulder mobility were assessed before and immediately following interventions. Group and time differences were analyzed using 2-way repeated-measures analysis of variance.

RESULTS

Greater changes in GH IR ROM (6°, P < .001), HA ROM (10°, P < .001), and shoulder mobility (-2 cm, P = .018) were observed in the SWM group than in the stretching group, although significant increases were observed in GH IR ROM (SWM group, P < .001; stretching group, P < .001), HA ROM (SWM group, P < .001; stretching group, P = .042), and shoulder mobility (SWM group, P < .001; stretching group, P < .001) after both interventions.

CONCLUSION

This study shows that SWM could be a useful exercise for shoulder ROM recovery in individuals with GH IR deficits.

Rotator interval closure: inconsistent techniques and its association with anterior instability. A literature review

The Rotator interval (RI) is an anatomic space in the anterosuperior part of the glenohumeral joint. An incompetent or lax RI has been implicated in various conditions of shoulder instability and therefore RI has been frequently touted as an area that is important in preserving stability of the shoulder. Biomechanical studies have shown that repair of RI ligamentous and capsular structures decreases glenohumeral joint laxity in various directions. Clinical studies have reported successful outcomes after repair or plication of these structures in patients undergoing shoulder stabilization procedures. Although varieties of methods have been described for its closure, the optimal surgical technique is unclear with various inconsistencies in incorporation of the closure tissue. This in particular makes the analysis of the RI closure very difficult. The purposes of this study are to review the structures of the RI and their contribution to shoulder instability, to discuss the biomechanical and clinical effects of plication of RI structures in particular to anterior glenohumeral instability, to delineate the differences between an arthroscopic and open RI closure. Additionally, we have proposed a new classification system describing various techniques used during RI closure.

Rehabilitation of symptomatic atraumatic degenerative rotator cuff tears: A clinical commentary on assessment and management

STUDY DESIGN

Clinical Commentary.

INTRODUCTION

Atraumatic rotator cuff (RC) disease, is one of the most common cause of shoulder pain, which encompasses a continuum from tendinopathy to full thickness cuff tears. Extrinsic, intrinsic and environmental factors have been implicated in the pathophysiology of this disorder, affecting the clinical presentation of symptoms including pain and irritability. Successful rehabilitation of symptomatic atraumatic degenerative rotator cuff (SADRC) tears must address the underlying mechanisms causing dysfunction and correct modifiable factors.

PURPOSE OF THE STUDY

The purpose of this paper is to review the shoulder complex anatomy, introduce atraumatic degenerative RC pathology, differentiate between symptomatic and asymptomatic degenerative RC tears, propose an assessment and introduce the Rotator Cuff Protocol 1 (RCP1) designed by the clinical reasoning of one of the lead authors (LW) as a rehabilitation management approach for those clients who present with SADRC tears.

METHODS/RESULTS/DISCUSSION

N/A for clinical commentary.

CONCLUSIONS

The ability to identify SADRC tears should consider shoulder anatomy, extrinsic, intrinsic and environmental factors, and the consideration for the natural history of atraumatic partial and full thickness tears in the general population. A thorough clinical history and examination, which includes shoulder symptom modification tests, allows the examiner to determine at what phase the patient may start their exercise program. The RCP1 is a program that has been used clinically by many therapists and clients over the years and research is underway to test this protocol in atraumatic rotator cuff disease including SADRC tears.

LEVEL OF EVIDENCE

5.

Glenohumeral internal rotation deficit in throwing athletes: current perspectives

Glenohumeral internal rotation deficit (GIRD) is an adaptive process in which the throwing shoulder experiences a loss of internal rotation (IR). GIRD has most commonly been defined by a loss of >20° of IR compared to the contralateral shoulder. Total rotational motion of the shoulder is the sum of internal and external rotation and may be more important than the absolute value of IR loss. Pathologic GIRD has been defined as a loss of IR combined with a loss of total rotational motion. The leading pathologic process in GIRD is posterior capsular and rotator-cuff tightness, due to the repetitive cocking that occurs with the overhead throwing motion. GIRD has been associated with numerous pathologic conditions, including posterior superior labral tears, partial articular-sided rotator-cuff tears, and superior labral anterior-to-posterior tears. The mainstay of treatment for patients with GIRD is posterior capsular stretching and strengthening to improve scapular mechanics. In patients who fail nonoperative therapy, shoulder arthroscopy can be performed. Arthroscopic surgery in the high-level throwing athlete should be to restore them to their functional baseline with the minimum amount of intervention possible.

Quantifying Range-of-Motion Changes Across 4 Simulated Measurements of the Glenohumeral Joint Posterior Capsule: An Exploratory Cadaver Study

Study Design Repeated-measures controlled laboratory cadaveric study. Background There is a lack of information about the most sensitive measure of glenohumeral joint posterior capsule length. Although maximum strains on the glenohumeral joint posterior capsule are observed in measurements combining glenohumeral joint flexion and internal rotation (IR), the range-of-motion (ROM) change after experimental contracture has never been compared across commonly used posterior capsular measurements. Objectives To evaluate the IR ROM change across 4 glenohumeral joint posterior capsule measurements after experimental capsule shrinkage using radiofrequency thermal energy. Methods Repeated measures of ROM across 4 test positions were compared after progressive experimental contracture of the posterior capsule in 12 cadaver shoulders. The ROM data were collected with a 3-D motion-capture device and evaluated using repeated-measures analysis of variance. Results Overall, ROM decreased after experimental capsular contracture. There was a significant interaction effect between test and condition (F = 4.26, P = .01). Two of the 4 tests, those that combined humeral flexion and IR, detected significant reductions in the ROM following experimental capsular contracture. Conclusion Greater ROM change was observed in tests combining flexion and IR of the glenohumeral joint after experimental posterior capsular contracture. These tests appear more responsive to capsular-length change. J Orthop Sports Phys Ther 2016;46(12):1080-1085. Epub 29 Oct 2016. doi:10.2519/jospt.2016.6440.

Biomechanical effects of rotator interval closure in shoulder arthroplasty

BACKGROUND

Subscapularis dysfunction remains a significant problem after shoulder arthroplasty. Published techniques have variable recommendations for placing a rotator interval closing suture in attempts to off-load the subscapularis repair site, the implications of which have yet to be examined in the literature. The goals of this study were to investigate the biomechanical benefit of the rotator interval closing suture on the subscapularis repair strength and to analyze the effect on shoulder range of motion.

METHODS

Sixteen matched cadaveric shoulders underwent a subscapularis tenotomy and shoulder arthroplasty. The subscapularis tenotomy was repaired, and motion at physiologic torsional force was recorded. One of each matched pair was randomly assigned to receive an additional rotator interval closure suture. Each specimen then underwent a standardized cyclic loading with measurement of gap formation and load to failure.

RESULTS

The rotator interval closing suture significantly increased the ultimate load to failure of the subscapularis repair (452 N vs. 219 N; P = .002) and decreased gap formation at the subscapularis repair site. Measurement of the shoulder motion showed no significant difference between shoulders with and without the rotator interval closing suture.

DISCUSSION

We report the additional biomechanical benefit that the rotator interval closing suture provides to the subscapularis repair site after shoulder arthroplasty. This suture acts to improve the load to failure of the subscapularis repair and to decrease gap formation under cyclic load. Furthermore, it does not detrimentally affect shoulder external rotation or overall arc of rotation. Our findings support the application of this off-loading technique after subscapularis repair during shoulder arthroplasty.

Shoulder Stiffness: Current Concepts and Concerns

Shoulder stiffness can be caused by various etiologies such as immobilization, trauma, or surgical interventions. The Upper Extremity Committee of ISAKOS defined the term "frozen shoulder" as idiopathic stiff shoulder, that is, without a known cause. Secondary stiff shoulder is a term that should be used to describe shoulder stiffness with a known cause. The pathophysiology of frozen shoulder is capsular fibrosis and inflammation with chondrogenesis, but the cause is still unknown. Conservative treatment is the primary choice. Pain control by oral medication, intra-articular injections with or without joint distension, and physical therapy are commonly used. In cases with refractory stiffness, manipulation under anesthesia or arthroscopic capsular release may be indicated. Because of various potential risks of complications with manipulations, arthroscopic capsular release is preferred. After the capsular release, stepwise rehabilitation is mandatory to achieve satisfactory outcome.

LEVEL OF EVIDENCE

Level V, evidence-based review.

Magnetic resonance imaging and short-term clinical results of severe frozen shoulder treated with manipulation under ultrasound-guided cervical nerve root block

BACKGROUND

We evaluated the magnetic resonance (MR) imaging findings and short-term clinical outcomes of severe idiopathic frozen shoulder treated with manipulation under ultrasound-guided cervical nerve root block (MUC).

METHODS

The subjects were 30 patients (average age, 55.2 years; 12 men, 18 women) with severe frozen shoulder. Severe idiopathic frozen shoulder was defined as follows: a range of motion (ROM) of ≤ 100° in forward flexion, ≤ 10° in external rotation, and at or below the fifth lumbar vertebral level in internal rotation. Before the manipulation, all patients had continued global ROM loss for at least 6 months. Before and after manipulation, they underwent MR imaging. MR images and clinical results were evaluated 1 month after the procedure.

RESULTS

In terms of the capsule tear pattern, MR imaging showed 14 midsubstance tears and 15 humeral avulsions of glenohumeral ligament-like lesions. An anterior labrum tear occurred in 4 shoulders, whereas 15 shoulders showed a bone bruise in the posterosuperior and anteromedial portions of the humeral head despite no humeral shaft fracture. There were significant improvements in the ROM, Constant-Murley score, American Shoulder and Elbow Surgeons score, and Numeric Rating Scale score from before treatment to 1 month after the procedure.

CONCLUSION

MR imaging of patients with severe frozen shoulder after MUC showed 29 capsule tears, 4 labrum tears, and 15 bone bruises of the humeral head. Approximately 50% of patients are likely to experience bone bruising after MUC. Long-term follow-up of these patients should be performed carefully.

Posterior Capsular Plication Constrains the Glenohumeral Joint by Drawing the Humeral Head Closer to the Glenoid and Resisting Abduction

BACKGROUND

Shoulder pain is a common problem, with 30% to 50% of the American population affected annually. While the majority of these shoulder problems improve, there is a high rate of recurrence, as 54% of patients experience persistent symptoms 3 years after onset.

PURPOSE

Posterior shoulder tightness has been shown to alter glenohumeral (GH) kinematics. Clinically, posterior shoulder contractures result in a significant loss of internal rotation and abduction (ABD). In this study, the effect of a posterior capsular contracture on GH kinematics was investigated using an intact cadaveric shoulder without violating the joint capsule or the rotator cuff.

STUDY DESIGN

Controlled laboratory study.

METHODS

Glenohumeral motion, humeral load, and subacromial contact pressure were measured in 6 fresh-frozen left shoulders during passive ABD from 60° to 100° using an automated robotic upper extremity testing system. Baseline values were compared with the experimental condition in which the full thickness of posterior tissues was plicated without decompressing the joint capsule.

RESULTS

Posterior soft tissue plication resulted in increased compression between the humeral head and the glenoid (axial load) at 90° of ABD. Throughout ABD, the posterior contracture increased the anterior and superior moment on the humeral head, but it did not change the GH kinematics in this intact model. As a result, there was no increase in the subacromial contact pressure during ABD with posterior plication.

CONCLUSION

In an intact cadaveric shoulder, posterior contracture does not alter GH motion or subacromial contact pressure during passive ABD. By tightening the soft tissue envelope posteriorly, there is an increase in compressive load on the articular cartilage and anterior/superior force on the humeral head. These findings suggest that subacromial impingement in the setting of a posterior soft tissue contracture may result from alterations in scapulothoracic motion, not changes in GH kinematics.

CLINICAL RELEVANCE

This investigation demonstrates that posterior capsular plication increases the axial load on the shoulder joint during ABD. While a significant difference from baseline was observed in the plicated condition, posterior capsular plication did not change GH motion or subacromial contact pressure significantly.

Pediatric and adolescent shoulder instability

Instability of the shoulder is a common issue faced by sports medicine providers caring for pediatric and adolescent patients. A thorough history and physical examination can help distinguish traumatic instability from multidirectional or voluntary instability. A systematic understanding of the relevant imaging characteristics and individual patient disease and goals can help guide initial treatment. Given the high risk of recurrent instability, young, active patients who seek to return to competitive contact sports should consider arthroscopic stabilization after a first-time instability event. MDI should be treated initially with conservative rehabilitation. Patients who fail extensive conservative treatment may benefit from surgical stabilization. Arthroscopic techniques may now approach the results found from traditional open capsular shift procedures. Future studies should be designed to examine the outcomes in solely pediatric and adolescent populations after both conservative and operative treatment of shoulder instability.

Anterior glenohumeral instability: a pathology-based surgical treatment strategy

The glenohumeral joint is the most frequently dislocated major joint, and most cases involve an anterior dislocation. Young male athletes competing in contact sports are at especially high risk of recurrent instability. Surgical timing and selection of surgical technique continue to be debated. Full characterization of the injury requires an accurate history and physical examination. Diagnostic imaging assists in identifying the underlying anatomic lesions, which range from no discernible lesion to significant bone loss of the glenoid or humeral head and/or capsulolabral stretching or avulsion from the glenoid or humerus. Historically, open Bankart repair has been considered to be the standard method of managing capsulolabral injuries, but comparable results have been achieved with arthroscopic techniques. In the setting of anterior glenoid bone loss >20% of the articular surface, iliac crest bone grafting or coracoid transfer via the Bristow or Latarjet procedures has demonstrated satisfactory outcomes. Favorable results have been reported with bone grafting or remplissage for engaging Hill-Sachs lesions and those that affect >30% of the humeral circumference.

Role of the superior labrum after biceps tenodesis in glenohumeral stability

BACKGROUND

Little is known about the role that a torn superior labrum (SLAP) plays in glenohumeral stability after biceps tenodesis. This biomechanical study evaluated the contribution of a type II SLAP lesion to glenohumeral translation in the presence of biceps tenodesis. The authors hypothesize that subsequent to biceps tenodesis, a torn superior labrum does not affect glenohumeral stability and therefore does not require anatomic repair in an overhead throwing athlete.

METHODS

Baseline anterior, posterior, and abduction and maximal external rotation glenohumeral translation data were collected from 20 cadaveric shoulders. Translation testing was repeated after the creation of anterior (n = 10) and posterior (n = 10) type II SLAP lesions. Translation re-evaluation after biceps tenodesis was performed for each specimen. Finally, anatomic SLAP lesion repair and testing were performed.

RESULTS

Anterior and posterior SLAP lesions led to significant increases in glenohumeral translation in all directions (P < .0125). Biceps tenodesis showed no significance in stability compared with SLAP alone (P > .0125). Arthroscopic repair of anterior SLAP lesions did not restore anterior translation compared with the baseline state (P = .0011) but did restore posterior (P = .823) and abduction and maximal external rotation (P = .806) translations. Repair of posterior SLAP lesions demonstrated no statistical difference compared with the baseline state (P > .0125).

CONCLUSIONS

With no detrimental effect on glenohumeral stability in the presence of a SLAP lesion, biceps tenodesis may be considered a valid primary or revision surgery for patients suffering from symptomatic type II SLAP tears. However, biceps tenodesis should be considered with caution as the primary treatment of SLAP lesions in overhead throwing athletes secondary to its inability to completely restore translational stability.

MR arthrography including abduction and external rotation images in the assessment of atraumatic multidirectional instability of the shoulder

OBJECTIVE

To evaluate diagnostic signs and measurements in the assessment of capsular redundancy in atraumatic multidirectional instability (MDI) of the shoulder on MR arthrography (MR-A) including abduction/external rotation (ABER) images.

METHODS

Twenty-one MR-A including ABER position of 20 patients with clinically diagnosed MDI and 17 patients without instability were assessed by three radiologists. On ABER images, presence of a layer of contrast between the humeral head (HH) and the anteroinferior glenohumeral ligament (AIGHL) (crescent sign) and a triangular-shaped space between the HH, AIGHL and glenoid (triangle sign) were evaluated; centring of the HH was measured. Anterosuperior herniation of the rotator interval (RI) capsule and glenoid version were determined on standard imaging planes.

RESULTS

The crescent sign had a sensitivity of 57 %/62 %/48 % (observers 1/2/3) and specificity of 100 %/100 %/94 % in the diagnosis of MDI. The triangle sign had a sensitivity of 48 %/57 %/48 % and specificity of 94 %/94 %/100 %. The combination of both signs had a sensitivity of 86 %/90 %/81 % and specificity of 94 %/94 %/94 %. A positive triangle sign was significantly associated with decentring of the HH. Measurements of RI herniation, RI width and glenoid were not significantly different between both groups.

CONCLUSIONS

Combined assessment of redundancy signs on ABER position MR-A allows for accurate differentiation between patients with atraumatic MDI and patients with clinically stable shoulders; measurements on standard imaging planes appear inappropriate.

KEY POINTS

MR arthrography has the possibility to accurately identify patients with atraumatic MDI. Imaging of the shoulder in abduction and external rotation provides additive information. Capsular enlargement of the shoulder can be diagnosed on MR arthrography.

Frozen shoulder - A stiff problem that requires a flexible approach

Frozen shoulder is a specific, painful and debilitating condition effecting patients mainly in middle age. While it has been recognised for over 100 years, it is still mis-diagnosed, with a natural history that is poorly understood and with limited evidence for the efficacy for various treatments. This review considers what is known about this common painful condition and the treatments available.

Clinical implications of scapular dyskinesis in shoulder injury: the 2013 consensus statement from the 'Scapular Summit'

The second international consensus conference on the scapula was held in Lexington Kentucky. The purpose of the conference was to update, present and discuss the accumulated knowledge regarding scapular involvement in various shoulder injuries and highlight the clinical implications for the evaluation and treatment of shoulder injuries. The areas covered included the scapula and shoulder injury, the scapula and sports participation, clinical evaluation and interventions and known outcomes. Major conclusions were (1) scapular dyskinesis is present in a high percentage of most shoulder injuries; (2) the exact role of the dyskinesis in creating or exacerbating shoulder dysfunction is not clearly defined; (3) shoulder impingement symptoms are particularly affected by scapular dyskinesis; (4) scapular dyskinesis is most aptly viewed as a potential impairment to shoulder function; (5) treatment strategies for shoulder injury can be more effectively implemented by evaluation of the dyskinesis; (6) a reliable observational clinical evaluation method for dyskinesis is available and (7) rehabilitation programmes to restore scapular position and motion can be effective within a more comprehensive shoulder rehabilitation programme.

The effect of glenohumeral internal rotation deficit due to posterior capsular contracture on passive glenohumeral joint motion

BACKGROUND

To date, no study has investigated the biomechanical consequences of glenohumeral internal rotation deficit (GIRD) at values seen in symptomatic athletes. Hypothesis/

PURPOSE

The purpose of this study was to determine the biomechanical changes that occur with a full spectrum of GIRD in a cadaveric model with passive loading. We hypothesized that there is a critical percentage of GIRD that will result in a decrease in posterior glenohumeral translation and shift of the humeral head apex at the extreme ranges of motion.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six specimens were tested using the following conditions: (1) native state ("intact"); (2) after external rotation (ER) stretch ("stretched"); and (3) GIRD of 5%, 10%, 15%, and 20%. For each condition, maximum ER, maximum internal rotation (IR), and total range of motion were measured. Kinematic data were obtained to determine the position of the humeral head apex (HHA), the highest point on the articular surface of the humeral head, relative to the geometric center of the glenoid. The amount of translation was measured in the anterior, posterior, superior, and inferior directions.

RESULTS

External rotation significantly increased compared with the intact condition for the stretched and 5% GIRD states, and IR decreased significantly beginning with 5% GIRD. At maximum ER, the HHA shifted significantly in the superior direction compared with the intact condition for all GIRD states, and at maximum IR, the HHA shifted significantly in the inferior direction compared with the intact and stretched conditions starting at 10% GIRD. The amount of posterior translation decreased significantly starting at 10% GIRD, and the amount of inferior translation decreased significantly starting at 20% GIRD.

CONCLUSION

Biomechanical changes of passive glenohumeral joint motion occur in the glenohumeral joint with as little as 5% GIRD.

CLINICAL RELEVANCE

Biomechanical changes of passive glenohumeral joint motion are noted with as little as 5% GIRD in this cadaveric model, and as the amount of GIRD increases, more substantial effects are noted.

Posterior glenohumeral joint capsule contracture

Glenohumeral joint posterior capsule contracture may cause shoulder pain by altering normal joint mechanics. Contracture is commonly noted in throwing athletes but can also be present in nonthrowers. The cause of contracture in throwing athletes is assumed to be a response to the high amount of repetitive tensile force placed on the tissue, whereas the mechanism of contracture in nonthrowers is unknown. It is likely that mechanical and cellular processes interact to increase the stiffness and decrease the compliance of the capsule, although the exact processes that cause a contracture have not been confirmed. Cadaver models have been used to study the effect of posterior capsule contracture on joint mechanics and demonstrate alterations in range of motion and in humeral head kinematics. Imaging has been used to assess posterior capsule contracture, although standard techniques and quantification methods are lacking. Clinically, contracture manifests as a reduction in glenohumeral internal rotation and/or cross body adduction range of motion. Stretching and manual techniques are used to improve range of motion and often decrease symptoms in painful shoulders.

Arthroscopic capsular plication for microtraumatic anterior shoulder instability in overhead athletes

BACKGROUND

Extreme loading conditions at the glenohumeral joint during overhead athletic activities can result in both soft tissue and osseous adaptative changes at the shoulder. Subtle alterations in the stabilizing structures may lead to anterior instability and debilitating shoulder pain with subsequent inability to participate in athletics. There is currently a paucity of data documenting clinical outcomes after arthroscopic capsular plication in overhead athletes who demonstrate objective findings of pain and anterior instability on physical examination.

PURPOSE

To evaluate outcomes after arthroscopic capsular plication for anterior instability in overhead athletes with an emphasis on postoperative range of motion, postoperative shoulder function, and return to sport.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The authors identified 20 overhead athletes with debilitating shoulder pain and a failed trial of nonoperative management who underwent arthroscopic capsular plication (12 suture plication, 8 suture anchor plication) for anterior instability related to isolated capsular redundancy. Patients were evaluated with the Single Assessment Numerical Evaluation (SANE) and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow Score, and they were interviewed to determine the rate of return to athletic activity. Failures of treatment included patients who demonstrated debilitating pain that precluded return to sport.

RESULTS

At a mean follow-up of 3.6 years (range, 2.0-5.5 years), 18 (90%) patients returned to overhead sports, with 17 (85%) at their preinjury level. The mean (SD) SANE score was 86 (17.5%; range, 30%-100%), and the mean (SD) KJOC score was 82 (18.2; range, 28-100). When compared with the contralateral extremity, there were no significant differences in glenohumeral range of motion. Two patients with associated rotator cuff injury experienced persistent pain with overhead activity and were unable to return to sport, representing a 10% failure rate.

CONCLUSION

Arthroscopic capsular plication for anterior instability related to isolated capsular redundancy is an effective procedure that yields a high rate of patient satisfaction and return to overhead athletic activity with an acceptably low failure rate. Patients with associated rotator cuff injury may be at higher risk for treatment failure.

Effects of combined anterior and posterior plication of the glenohumeral ligament complex for the repair of anterior glenohumeral instability: a biomechanical study

BACKGROUND

Arthroscopic repair techniques for anterior instability most commonly address only the anterior band of the inferior glenohumeral ligament. This study quantitatively evaluated and compared the combined anterior and posterior arthroscopic plication by repairing both the anterior and posterior bands of the inferior glenohumeral ligament with the anterior arthroscopic plication alone.

MATERIALS AND METHODS

Six cadaveric shoulders were tested in 60° of glenohumeral abduction with 22 N of compressive force in the coronal plane for intact, after anterior capsular stretching, after anterior repair, and after posterior arthroscopic repair. Range of motion, glenohumeral translation, and glenohumeral kinematics throughout the rotational range of motion were measured with a MicroScribe 3DLX (Immersion, San Jose, CA, USA). Glenohumeral contact pressure and area were measured with a pressure measurement system (Tekscan Inc, South Boston, MA, USA).

RESULTS

Stretching the anterior capsule significantly increased external rotation and anterior translation (P < .05). After anterior plication, external rotation was restored to the intact condition, and anterior translation was significantly decreased compared with stretched condition (P < .05). The combined anterior and posterior plication significantly decreased internal rotation compared with the intact condition. The anterior plication shifted the humeral head posterior in external rotation, whereas the combined anterior and posterior plication shifted the humeral head anterior in internal rotation (P < .05). Both repairs led to a decrease in glenohumeral contact area at 45° external rotation (P < .07).

CONCLUSIONS

The addition of a posterior plication to anterior plication for anterior instability has no biomechanical advantage over a typical arthroscopic anterior repair for anterior glenohumeral instability.

Frozen shoulder

Frozen shoulder is commonly encountered in general orthopaedic practice. It may arise spontaneously without an obvious predisposing cause, or be associated with a variety of local or systemic disorders. Diagnosis is based upon the recognition of the characteristic features of the pain, and selective limitation of passive external rotation. The macroscopic and histological features of the capsular contracture are well-defined, but the underlying pathological processes remain poorly understood. It may cause protracted disability, and imposes a considerable burden on health service resources. Most patients are still managed by physiotherapy in primary care, and only the more refractory cases are referred for specialist intervention. Targeted therapy is not possible and treatment remains predominantly symptomatic. However, over the last ten years, more active interventions that may shorten the clinical course, such as capsular distension arthrography and arthroscopic capsular release, have become more popular. This review describes the clinical and pathological features of frozen shoulder. We also outline the current treatment options, review the published results and present our own treatment algorithm.

Anatomic and biomechanical fundamentals of the thrower shoulder

The act of throwing requires proper functioning and timing of the entire kinetic chain musculature to generate a coordinated movement pattern for ball delivery. The role of the shoulder complex is vital in the transmission of force from the lower extremities and trunk to the arm and hand. A review of the anatomic and biomechanical factors of the shoulder girdle will be discussed as it pertains to the thrower. An understanding of the relationship of the muscles, ligaments, and osseous structures is essential to the successful diagnosis and treatment of shoulder pathology and dysfunction.

Mechanisms of rotator cuff tendinopathy: intrinsic, extrinsic, or both?

The etiology of rotator cuff tendinopathy is multi-factorial, and has been attributed to both extrinsic and intrinsic mechanisms. Extrinsic factors that encroach upon the subacromial space and contribute to bursal side compression of the rotator cuff tendons include anatomical variants of the acromion, alterations in scapular or humeral kinematics, postural abnormalities, rotator cuff and scapular muscle performance deficits, and decreased extensibility of pectoralis minor or posterior shoulder. A unique extrinsic mechanism, internal impingement, is attributed to compression of the posterior articular surface of the tendons between the humeral head and glenoid and is not related to subacromial space narrowing. Intrinsic factors that contribute to rotator cuff tendon degradation with tensile/shear overload include alterations in biology, mechanical properties, morphology, and vascularity. The varied nature of these mechanisms indicates that rotator cuff tendinopathy is not a homogenous entity, and thus may require different treatment interventions. Treatment aimed at addressing mechanistic factors appears to be beneficial for patients with rotator cuff tendinopathy, however, not for all patients. Classification of rotator cuff tendinopathy into subgroups based on underlying mechanism may improve treatment outcomes.

[Advances in arthroscopic capsular labrum repair in ventral shoulder instability]

Current data show that the majority of patients in Germany with shoulder instability caused by soft tissue lesions are treated arthroscopically. The published redislocation rates in retrospective studies are less than 10%. Currently most surgeons prefer to use special strong suture materials and bioabsorbable suture anchors with a trend for knotless anchors. Some authors have published special techniques for labrum repair including double row fixation to increase the pull out force of the sutures but further prospective studies are necessary to prove whether these techniques can reduce the redislocation rate. In cases of extended anterior pouch of the capsule and in non-traumatic instability, capsular plication and interval closure can be indicated. There are still no clear objective parameters concerning indications or amount of plication and interval closure.

Open capsular shift: there still is a role!

As our understanding of the pathoanatomy of glenohumeral instability has improved, surgical techniques for the treatment of anterior instability have progressed. Many stabilization procedures are now successfully performed arthroscopically; open capsular shift, however, continues to play an important role in the management of instability in certain patients, providing an accurate and selective means of capsular plication. When performed with proper surgical technique, shoulder range of motion can be preserved with low recurrence rates and high subjective satisfaction, making the open capsular shift a durable and effective option in the modern management of shoulder instability.

Shoulder instability in patients with joint hyperlaxity

Generalized ligamentous hyperlaxity and glenohumeral joint instability are common conditions that exhibit a spectrum of diverse clinical forms and may coexist in the same patient. No single diagnostic test can confirm the presence of these disorders, and a careful clinical assessment is important. Unlike patients with traumatic shoulder instability, patients with hyperlaxity and instability are more likely to experience episodes of recurrent subluxation than they are to have recurrent dislocation. They are more likely to have instability in more than one anatomic plane, and they usually do not have the soft-tissue and osseous lesions associated with traumatic instability. Shoulder symptoms in a patient with hyperlaxity are not always due to instability; other pathological conditions may coexist, with rotator cuff impingement being the most common. Most patients with hyperlaxity have a reduction in instability symptoms after nonoperative treatment, including physical therapy, activity modification, and additional psychological support when necessary. Operative treatment provides reproducibly good results for patients with hyperlaxity who do not respond to a prolonged program of nonoperative measures. Open inferior capsular shift remains the gold standard of operative treatment, although arthroscopic capsular shift and plication procedures are now producing comparable results. Thermal capsulorrhaphy is associated with unacceptably high failure rates and postoperative complications and cannot be recommended as a treatment.

The effect of posterior capsular tightening on peak subacromial contact pressure during simulated active abduction in the scapular plane

HYPOTHESIS

Our hypothesis was that tightening of the posterior capsule would lead to increased subacromial pressure and increased superior translation during active abduction in the scapular plane.

BACKGROUND

Subacromial impingement syndrome is a painful condition that occurs during overhead activities as the rotator cuff is compressed in the subacromial space. Unrecognized secondary causes of subacromial impingement may lead to treatment failure. Posterior capsular tightness, believed to alter glenohumeral joint kinematics, is often cited as a secondary cause of SI; however, scientific evidence is lacking. The primary objective of this study was to evaluate the effect of posterior capsular tightening on peak subacromial pressure during abduction in the scapular plane.

MATERIALS AND METHODS

Ten fresh frozen shoulder specimens from deceased donors were mounted on a custom shoulder simulator. With the scapula fixed, the deltoid and rotator cuff muscles were loaded in discrete static steps with a constant ratio to elevate the humerus in the scapular plane. The treatment order (no tightening, 1-cm, and 2-cm tightening of the posterior capsule) was randomly assigned to each specimen. Peak subacromial contact pressure and glenohumeral kinematics at the peak pressure position were compared using a repeated measures analysis of variance.

RESULTS

Peak subacromial pressures (mean +/- standard deviation) were similar between treatment groups: 345 +/- 152, 410 +/- 213, and 330 +/- 164 kPa for no tightening, 1-cm, and 2-cm tightening of the posterior capsule respectively (P > .05). No significant differences were found for superior or anterior translations at the peak pressure position (P > .05).

DISCUSSION

Posterior capsular tightening, as a sole variable, did not contribute to a significant increase in peak subacromial pressure during abduction in the scapular plane. A similar study simulating active forward flexion is necessary to fully characterize the contribution of posterior capsular tightness to subacromial impingement.

CONCLUSION

Tightening of the posterior capsule did not increase subacromial pressure, or increase superior or anterior translation during abduction in the scapular plane.

Influence of humeral torsion on interpretation of posterior shoulder tightness measures in overhead athletes

OBJECTIVE

To measure the influence of humeral torsion on interpretation of clinical indicators of posterior shoulder tightness in overhead athletes.

DESIGN

Cross-sectional control group comparison.

SETTING

A university-based sports medicine research laboratory.

PARTICIPANTS

Twenty-nine healthy intercollegiate baseball players and 25 college-aged control individuals with no history of participation in overhead athletics were enrolled.

INTERVENTION

In all participants, bilateral humeral rotation and humeral horizontal adduction variables were measured with a digital inclinometry. Bilateral humeral torsion was measured with ultrasonography.

MAIN OUTCOME MEASURES

Group and limb comparisons were made for clinical indicators of posterior shoulder tightness (humeral rotation and horizontal adduction variables) and humeral torsion variables. The relationship between humeral torsion and clinical indicators of posterior shoulder tightness were established.

RESULTS

The dominant limb of the baseball players demonstrated greater humeral torsion, and less internal rotation and total rotation range of motion, compared with control participants and the nondominant limb in both groups. Once corrected for torsion, no group or limb differences in internal rotation were present. Statistically significant relationships existed between the amount of humeral torsion and measures of posterior shoulder tightness.

CONCLUSIONS

Although limb differences in clinical indicators of posterior tightness exist in healthy overhead athletes, these measures appear to be influenced by humeral torsion rather than soft tissue tightness. Once torsion is accounted for, the limb differences observed clinically were minimal in healthy overhead athletes. When possible, accounting for humeral torsion when interpreting clinical measures of posterior shoulder tightness may aid in treatment decisions.